U.S. patent number 7,361,172 [Application Number 10/455,486] was granted by the patent office on 2008-04-22 for ultrasonic device and method for tissue coagulation.
This patent grant is currently assigned to Sound Surgical Technologies LLC. Invention is credited to William C. Cimino.
United States Patent |
7,361,172 |
Cimino |
April 22, 2008 |
Ultrasonic device and method for tissue coagulation
Abstract
An ultrasonic surgical device for the coagulation of animal
tissue having an ultrasonic applicator and a movable jaw with a jaw
surface adjacent the distal portion of the ultrasonic applicator
for movement toward the applicator to a closed position at a
predefined clearance of between about 0.075 to about 1.9
millimeters from the applicator. The device may also include a
mechanical cutting element that can be extended into the clearance
to cut the tissue and means to vary the predefined clearance
without removing the applicator from the patient. Tissue
coagulating and cutting can be maximized and performed separately
and can be easily monitored by the surgeon.
Inventors: |
Cimino; William C. (Louisville,
CO) |
Assignee: |
Sound Surgical Technologies LLC
(Louisville, CO)
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Family
ID: |
29712231 |
Appl.
No.: |
10/455,486 |
Filed: |
June 4, 2003 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20040102801 A1 |
May 27, 2004 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60386119 |
Jun 4, 2002 |
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Current U.S.
Class: |
606/27; 606/1;
606/49; 606/40; 601/3; 601/2 |
Current CPC
Class: |
A61N
7/02 (20130101); A61B 2017/00504 (20130101); A61B
2017/320093 (20170801); A61B 2017/320094 (20170801); A61B
2017/320095 (20170801) |
Current International
Class: |
A61B
18/04 (20060101) |
Field of
Search: |
;606/37,40 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2032501 |
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Jan 1972 |
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DE |
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7705947 |
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Jun 1977 |
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DE |
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2 355 521 |
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Feb 1978 |
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FR |
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61-128954 |
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Jun 1986 |
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JP |
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232948 |
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Sep 1989 |
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JP |
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737735 |
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May 1980 |
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SU |
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PCT/US03/17677 |
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Jun 2003 |
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WO |
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Other References
Spivak, H.; Richardson, W.; Hunter, J.; "The use of bipolar
cautery, laparosonic coagulating shears, and vascular clips for
hemostasis of small and medium-sized vessels,"Surgical Endoscopy
Feb. 1998; 12(2):183-5. cited by other .
Landman, J. et al., "Comparison of the Ligasure System, Bipolar
electrosurgery, Harmonic scalpel, titanium clips, Endo-FIA, and
sutures for laparoscopicvascular control in a porcine model,"
Presensted at SAGES meeting, poster session, St. Louis, MO. Apr.
19-Apr. 21, 2001. cited by other .
PCT Written Opinion for PCT/US03/17677 dated Jun. 17, 2004. cited
by other .
PCT International Preliminary Examination Report dated Oct. 28,
2005. cited by other .
Supplementary European Serach Report for EP 03 73 6854 dated Oct.
5, 2007. cited by other .
Office Action in Chinese Counterpart Application No. 03818709.4;
Jun. 2, 2006. cited by other .
Office Action in Australian Counterpart Application No. 2003237398;
Sep. 18, 2007. cited by other.
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Primary Examiner: Casler; Brian L.
Assistant Examiner: Kish; James
Attorney, Agent or Firm: Pereyra; Rene A. Merchant &
Gould P.C.
Parent Case Text
This application claims the benefit of priority from U.S.
provisional patent application Ser. No. 60/386,119, filed Jun. 4,
2002.
Claims
The invention claimed is:
1. An ultrasonic surgical apparatus for the coagulation of animal
tissue having a handle for manipulation by a surgeon, an ultrasonic
transducer for generating ultrasonic vibration, and an ultrasonic
applicator attached to the ultrasonic transducer and extending from
the handle for delivery of ultrasonic vibrations to the animal
tissue, wherein said apparatus further comprises: a distal portion
on the ultrasonic applicator having a generally round cross-section
with a diameter between approximately 2 and 6 millimeters to
provide a broad surface for coagulation and to avoid cutting of the
animal tissue; an elongated support member releasably attached to
the surgical handle and extending to the distal portion of the
ultrasonic applicator; a movable jaw with a jaw surface attached to
the elongated support member adjacent the distal portion of the
ultrasonic applicator for movement toward said distal portion to a
closed position at a predefined clearance of between about 0.075 to
about 1.9 millimeters, from said distal portion, wherein the
movable jaw is configured to grasp and hold the animal tissue
during coagulation while allowing the animal tissue to flow and
coagulate; and a stop for establishing the predefined
clearance.
2. The ultrasonic surgical apparatus of claim 1 wherein the
predefined clearance is between about 0.075 and about 0.75
millimeters.
3. The ultrasonic surgical apparatus of claim 2 wherein the jaw
surface in the closed position is generally parallel with the
surface of the elongated support member.
4. The ultrasonic surgical device of claim 2 wherein the jaw
surface is concave.
5. The ultrasonic surgical device of claim 2 wherein the jaw
surface is convex.
6. The ulstrasonic surgical device of claim 2 wherein the jaw
surface is flat.
7. The ultrasonic surgical device of claim 2 wherein the stop is
located on the elongated support member.
8. The ultrasonic surgical device of claim 2 wherein the stop is
located on the handle of the ultrasonic surgical device.
9. The ultrasonic surgical device of claim 2 wherein the
predetermined clearance may be varied without requiring removal of
the ultrasonic surgical device from the patient during a medical
procedure.
10. An ultrasonic surgical apparatus for the treating of animal
tissue having a handle for manipulation by a surgeon an ultrasonic
transducer for generating ultrasonic vibration, and an ultrasonic
applicator attached to the ultrasonic transducer and extending from
the handle for delivery of ultrasonic vibrations to the animal
tissue, wherein said apparatus further comprises: a distal portion
on the ultrasonic applicator having a generally round cross-section
with a diameter between approximately 2 and 6 millimeters to
provide a broad surface for coagulation and to avoid cutting of the
animal tissue; an elongated support member releasably attached to
the surgical handle and extending to the distal portion of the
ultrasonic applicator; a movable jaw with a jaw surface attached to
the elongated support member adjacent the distal portion of the
ultrasonic applicator for movement toward said distal portion to a
closed position at a predefined clearance of between about 0.075 to
about 1.9 millimeters from said distal portion, wherein the movable
jaw is configured to grasp and hold the animal tissue during
coagulation while allowing the animal tissue to flow and coagulate
as the animal tissue is heated by vibration of the ultrasonic
applicator; a stop for establishing the predefined clearance; and a
mechanical cutting device for movement parallel to the ultrasonic
applicator to cut the animal tissue located between the ultrasonic
applicator and the clamp.
11. The ultrasonic surgical apparatus of claim 10 wherein the
predefined clearance is between about 0.075 and about 0.75
millimeters.
12. The ultrasonic surgical apparatus of claim 11 wherein the jaw
surface in the closed position is generally parallel with the
surface of the elongated support member.
13. The ultrasonic surgical device of claim 11 wherein the jaw
surface is concave.
14. The ultrasonic surgical device of claim 11 wherein the jaw
surface is convex.
15. The ultrasonic surgical device of claim 11 wherein the jaw
surface is flat.
16. The ultrasonic surgical device of claim 11 wherein the stop is
located on the elongated support member.
17. The ultrasonic surgical device of claim 11 wherein the stop is
located on the handle of the ultrasonic surgical device.
18. The ultrasonic surgical device of claim 11 wherein the
predetermined clearance may be varied without requiring removal of
the ultrasonic surgical device from the patient during a medical
procedure.
19. The ultrasonic surgical device of claim 11 wherein the
mechanical cutting device is a blade.
20. A method for the surgical coagulation of animal tissue
comprising: locating a portion of the animal tissue between an
ultrasonic application having a generally round cross-section with
a diameter between approximately 2 and 6 millimeters to provide a
broad surface for coagulation and to avoid cutting of the animal
tissue; and a clamp located adjacent the ultrasonic tissue; moving
the clamp toward the ultrasonic applicator to a predefined
clearance of between about 0.075 to about 1.9 millimeters from the
ultrasonic applicator to grasp and hold the desired tissue during
coagulation while providing a zone for tissue flow and coagulation,
wherein the predetermined clearance is established by a stop; and
applying ultrasonic vibrations to the portion of the tissue via the
ultrasonic applicator sufficient to cause coagulation of the
tissue.
21. The method of claim 20 wherein the predefined clearance is
about 0.075 and about 0.75 millimeters.
22. The method of claim 21 wherein the predetermined clearance may
be varied without requiring removal of the ultrasonic surgical
device from the patient during a medical procedure.
23. A method for-surgically treating animal tissue with minimal
bleeding comprising: locating the animal tissue between an
ultrasonic applicator having a generally round cross-section with a
diameter between approximately 2 and 6 millimeters to provide a
broad surface for coagulation and to avoid cutting of the animal
tissue; moving the clamp toward the ultrasonic applicator to a
predefined clearance of between about 0.075 to about 1.9
millimeters from the ultrasonic applicator to grasp and hold the
animal tissue during coagulation while providing a zone for tissue
flow and coagulation as the animal tissue is heated by vibration of
the ultrasonic applicator, wherein the predetermined clearance is
established by a stop; applying ultrasonic vibrations to the animal
tissue via the ultrasonic applicator sufficient to cause
coagulation of the animal tissue; and cutting said tissue after it
has been coagulated using a mechanical cutting device.
24. The method of claim 23 wherein the predefined clearance is
between about 0.075 and about 0.75 millimeters.
25. The method of claim 24 wherein the predetermined clearance may
be varied without requiring removal of the ultrasonic surgical
device from the patient during a medical procedure.
26. The method of claim 24 wherein the mechanical cutting device is
a blade.
Description
I. FIELD OF THE INVENTION
The present invention relates generally to surgical instruments,
and more particularly, to an ultrasonic surgical device for use in
coagulation of tissues of a patient.
II. BACKGROUND OF THE INVENTION
Hemostasis of bleeding or potentially bleeding tissues is of
premium importance in open or laparoscopic surgery. Several methods
are currently used to coagulate tissues to achieve the desired
hemostasis. Sutures are safe, reliable, and commonly used on larger
vessels or structures, but are difficult to use on small vessels or
structures or in situations involving diffuse bleeding. Monopolar
electrosurgery works by electrically heating and burning the tissue
to achieve coagulation. It is effective on the smaller vessels and
structures but may cause undesirable thermal trauma to adjacent
tissues due to stray electrical conduction in a wet surgical
environment. Bipolar electrosurgery also works by electrically
heating the tissues and provides improved control of stray
electrical conduction relative to monopolar electrosurgery. Bipolar
instruments may suffer from tissue adherence to the electrodes,
causing the coagulated tissue to be re-opened and bleed again as
the probes are removed. Ultrasonic instruments use frictional heat
generated by rapid vibration rubbing of the tissue to create
hemostasis.
Ultrasonic surgical devices for cutting and coagulation of tissue
are known. All of these devices utilize longitudinal vibrations in
an ultrasonic member to accomplish a desired surgical effect such
as cutting with simultaneous coagulation. Clamping mechanisms have
been disclosed which claim to improve cutting and coagulation
performance by enhancing the tissue contact between the vibrating
member and the clamp surface. U.S. Pat. Nos. 3,862,630 and
3,636,943, both to Balamuth, disclose two types of ultrasonic
surgical devices: a first device for simultaneously cutting and
coagulating tissue, and a second device for joining together layers
of tissue. The device for joining together layers of tissue has a
vibrating ultrasonic member and a clamp mechanism, the working
surface of the clamp mechanism being perpendicular to the direction
of the longitudinal vibrations of the tool, so that tissues are
compressed between the working surface of the clamp and the end
surface of the vibrating ultrasonic member. This "end-on" design
blocks tissue access to the clamped region between the ultrasonic
member and clamp mechanism from the axial direction, requiring that
tissue be accessed laterally, and thereby severely limits
application of the device for surgical application because tissue
cannot be accessed in a scissor-like fashion.
U.S. Pat. No. 5,322,055 to Davidson discloses an ultrasonic
surgical device for simultaneously cutting and coagulating tissue
having a vibrating ultrasonic member and a clamp mechanism, the
ultrasonic member having a surgical blade with an elongated edge
parallel to the axis of longitudinal vibration at the distal end of
the vibrating ultrasonic member. This patent alleges enhanced
cutting performance due to the surgical blade with the elongated
edge and also improves performance by providing tissue access to
the ultrasonic member and the clamp mechanism from the axial
direction. The clamp mechanism is designed to close completely
(i.e., touch) against the vibrating ultrasonic member to achieve
the described cutting and coagulation effects. The improved cutting
action in this design is allegedly caused by the vibration of the
surgical blade with an elongated edge and the complete closure of
the blade against the clamp mechanism.
U.S. Pat. No. 6,193,709 to Manna discloses an ultrasonic surgical
device for simultaneously cutting and coagulating tissue having a
vibrating ultrasonic member and a clamp mechanism, the ultrasonic
member having a blade at the distal end of the vibrating ultrasonic
member, the blade forming an acute angle with respect to the axis
of longitudinal vibration. The patent alleges that the angled
design enhances tissue contact between the clamp mechanism and the
blade during operation and thereby improves performance. The clamp
mechanism is designed to close completely (touch) against the
vibrating ultrasonic member to achieve the described cutting and
coagulation effects. Improved cutting action in this design is due
to the vibration of the blade with the acute angle with respect to
the axis of longitudinal vibration and the complete closure of the
blade against the clamp mechanism.
U.S. Pat. No. 6,193,709 to Miyawaki discloses an ultrasonic
surgical device for treatments such as incision and coagulation
having a vibrating ultrasonic member and a clamp having a follow-up
mechanism so that the clamp can follow a deflective displacement of
the distal end portion of the vibrating ultrasonic member. This
patent asserts that the follow-up mechanism eliminates potential
gaps between the vibrating ultrasonic member and the clamp
mechanism as the clamp mechanism is closed onto the vibrating
ultrasonic member, thereby improving grasping and treatment
performance. The clamp mechanism is designed to close completely
(i.e., touch) against the vibrating ultrasonic member to achieve
the described treatments such as incision and coagulation.
None of the patents discloses a device for limiting the closure of
the clamp mechanism relative to the vibrating ultrasonic member for
the purpose of creating a predetermined clearance there between so
that an improved coagulation effect is achieved. Holding the clamp
against the ultrasonic member in the prior art devices will
inevitably result in the cutting of the tissue. The surgeon has no
way of knowing how far the process has occurred from the intended
coagulation to undesirable cutting. Indeed, these prior art devices
are designed to achieve simultaneous cutting and coagulation as the
clamp closes completely against the vibrating ultrasonic member,
regardless of the shape of the jaw surface of the clamp mechanism
and the shape of the vibrating ultrasonic member. It is often
desirable in the course of surgery to coagulate tissue without
cutting. It is impossible to reliably separate these two processes
in the prior art devices. Thus, there is a need to improve the
coagulation performance of ultrasonic surgical devices and further
to provide independent cutting and coagulation capabilities.
Deficiencies in the performance of prior art coagulation devices
have been noted in the literature. (See, for example, Spivak H. et
al., "The Use of Bipolar Cautery, Laparsonic Coagulating Shears,
and Vascular Clips for Hemostatis of Small and Medium-sized
Vessels," Surgical Endoscopy, 12(2):183-85 (February 1998) and
Landman, J. (Washington University), "Comparison of the Ligasure
System, Bipolar Electrosurgery, Harmonic Scalpel, Titanium Clips,
Endo-GIA, and Sutures for Laparoscopic Vascular Control in a
Porcine Model," presented at the Society of American
Gastrointestinal Endoscopic Surgeons, St. Louis, Mo., (Apr. 10-21,
2001). Both of these studies included the ultrasonic laparosonic
coagulating shears ("LCS") manufactured and distributed by Johnson
& Johnson using technology believed to be covered by the
Davidson '055 Patent referenced above. Spivak et al. tested the
capability of the LCS device and others to coagulate small and
medium sized blood vessels in pigs by increasing the associated
blood pressure to the point of failure or a maximum load of 300 mm.
Hg. While the authors personally concluded that the devices "can be
considered safe," the devices were not uniformly successful. The
LCS device was successful in all of the "small vessel" tests but
had two complete failures in the twelve tests of medium-sized
vessels and two additional instances where the medium-sized vessel
commenced bleeding before the defined pressure limit was reached.
This is an unacceptable failure rate of 33%. As noted by the
authors, the LCS needs to be properly sized and the surgeon
properly trained in order to use the LCS successfully on
medium-sized vessels. In addition, the authors recommended that
"the surgeon have a good alternative method in case initial
hemostasis fails." Similarly, Landman compared various modalities
for sealing vessels. On arteries, the LCS succeeded 5/6 times for
an 83% success rate; on veins the LCS succeeded 3/6 times for a 50%
success rate. Thus, there is clearly a need for significant
improvement in a surgical coagulation device.
A means to substantially improve the coagulation performance of
ultrasonic surgical instruments has now been discovered. First, the
coagulation performance can be improved by separating the
coagulation and cutting functions of the instrument so that they
are done sequentially rather than simultaneously. Indeed, it has
proven helpful to perform the coagulation prior to the cutting
rather than simultaneously or in the opposite order. A sequential
approach allows time for the tissue to be coagulated and cooled so
that it sets before any cutting action occurs. Indeed, tissue
bleeding may be totally avoided in this manner. The present
invention accomplishes the sequential coagulating and cutting steps
with a single grasp of the instrument, meaning that the tissue
grasp does not have to be released to alter the instrument for
cutting purposes once coagulation is achieved. Second, the
coagulation performance is substantially improved by providing a
predefined clearance between a jaw surface and a vibrating
ultrasonic applicator so that a tissue flow will occur in a
carefully controlled manner. The "tissue flow" (i.e., the
propensity of the tissue to move plastically upon sufficient
heating) in the predefined clearance creates a zone of coagulated
tissue that is much less likely to re-bleed than tissue that is
simultaneously cut and coagulated with previously disclosed
methods. It has now been discovered that if the predefined
clearance is carefully controlled to be between about 0.075 to
about 1.9 millimeters, and preferably between about 0.075 and about
0.75 millimeters, then the most effective coagulation performance
is obtained. It has been found that if the predefined clearance is
less than about 0.075 mm, simultaneous cutting action may occur. If
the predefined clearance is greater than about 1.9 mm, it has been
found that insufficient tissue flow is achieved and complete
coagulation may not occur.
III. SUMMARY OF THE INVENTION
The present invention provides a novel, improved ultrasonic
surgical device for and method for coagulating tissue. The device
of the present invention has a surgical handle with an ultrasonic
transducer mounted therein for generating ultrasonic vibrations. An
ultrasonic applicator is attached to the ultrasonic transducer for
transmitting longitudinal ultrasonic vibrations and extends
distally from the surgical handle. The ultrasonic applicator is
generally and substantially round in cross-section at the distal
end and has a diameter between approximately 2 millimeters and 6
millimeters. A clamp with a jaw surface is supported on an
elongated support member that is releasably attached to the
surgical handle that generally surrounds the ultrasonic applicator
along its length. The clamp and jaw surface are designed so that
the clamp cannot be completely closed against the vibrating
ultrasonic applicator, but is stopped at a predefined clearance,
i.e., distance between the jaw surface and the vibrating ultrasonic
applicator. This predefined clearance provides a zone for
controlled tissue flow as the vibrating ultrasonic member heats the
tissue. The shape and thickness of the predefined clearance
determine the quality and final shape of the coagulated tissue. The
predefined clearance may be varied between between about 0.075 to
about 1.9 mm, and preferably between about 0.075 and about 0.75 mm,
depending on the type and structure of the targeted tissue to be
coagulated. The surgical device can include means for adjusting the
clearance within this range. Thus, the vibrating ultrasonic
applicator is not a vibrating "blade" and is not used for the
cutting of tissues, but only for improved coagulation. The zone of
controlled tissue flow also contributes to improved coagulation by
creating an improved coagulation effect and by avoiding
simultaneous cutting during coagulation. The thickness and shape of
the tissue flow is carefully controlled.
If a cutting capability is desired with the surgical device, a
separate non-ultrasonic cutting element may be provided that can be
advanced and retracted to accomplish the cutting function as a
separate step. The cutting element may be advanced after the
coagulation has been completed, and the jaw is still closed to the
maximum permitted extent. Preferably, the cutting element may be a
surgical blade with a sharpened leading edge that cuts the
coagulated tissue as it is advanced. Other forms of mechanical
cutting tools can be employed. The surgeon can wait to advance the
cutting tool until sufficient time has elapsed for the tissue to
have been coagulated and "cooled" to minimize bleeding during the
cutting process.
The device of the present invention may also be employed in an
improved method of coagulation comprising the application of
ultrasonic surgery via an applicator having a round cross-section
to tissue held by a clamp located at a fixed distance from the
applicator's surface. A surgical method may also be employed using
that coagulation method to coagulate or cauterize tissue prior to
cutting with a mechanical cutting tool attached to, but separate
from, the ultrasonic applicator.
Thus, the present invention provides an improved ultrasonic
surgical instrument and method for tissue coagulation alone or with
a separate cutting of tissue. To accomplish this, the present
invention includes an ultrasonic surgical instrument and method
with a predetermined clearance between the surfaces of a clamp
holding the tissue against a vibrating ultrasonic member having a
substantially circular cross-section so that controlled flow of the
tissue can occur without ultrasonic cutting. In addition, the
present invention includes an ultrasonic surgical instrument and
method where the cutting means is contained in the same instrument
but is independent of the ultrasonic vibrations. Other features or
variations of the present invention for improved coagulation may be
apparent to one skilled in the art from the enclosed specification,
drawings and claims.
The invention may be best understood by reference to the detailed
description of some preferred embodiments and the illustrations of
preferred embodiments in the accompanying figures.
IV. BRIEF DESCRIPTION OF THE DRAWINGS
The following drawings show specific embodiments that help
appreciate the novel features of the present invention.
FIG. 1a is a partial cut-away, side-view of one embodiment of the
device of the present invention. The drawing depicts the device
with the clamp in an open position and the mechanical cutting tool
in a retracted position.
FIG. 1b is a partial cut-away, side view of one embodiment of the
device of the present invention. The drawing depicts the device
with the clamp in the closed position and the mechanical cutting
tool in a retracted position.
FIG. 1c is a partial cut-away, side view of one embodiment of the
device of the present invention. The drawing depicts the device
with the clamp in the closed position and the mechanical cutting
tool in an advanced position for cutting.
FIG. 2 is detailed partial cut-away, side-view representation of
the distal portion of the is ultrasonic device including the
electronic applicator, clamp and mechanical cutting tool.
FIG. 3a is an end-on view of the ultrasonic device showing a clamp
with a concave jaw surface in the closed position.
FIG. 3b is an end-on view of the ultrasonic device showing a clamp
with a convex jaw surface in the closed position.
FIG. 3c is an end-on view of the ultrasonic device showing a clamp
with a flat jaw surface in the closed position.
FIG. 4 is a partial cut-away, side-view of one embodiment of the
device of the present invention in which the stop for establishing
the pre-defined clearance is located on the handle of the
ultrasonic device.
Common reference numerals have been used on all drawings for
convenience.
V. DETAILED DESCRIPTION
Referring to the drawings, FIG. 1a is a schematic representation of
one preferred embodiment of the invention. FIG. 1 illustrates a
partial cut-away view of the present invention including an
ultrasonic surgical instrument, generally designated 10. The
instrument has a surgical handle 11 to be held and manipulated by
the surgeon. The surgical handle 11 may be fabricated from either
machined or molded plastic components. An ultrasonic transducer 12
is mounted within the surgical handle 11 for generating ultrasonic
vibrations. The ultrasonic vibrations may be generated using any
common and well-known means such as the use of PZT crystals held in
compression.
An ultrasonic applicator 13 is attached to the ultrasonic
transducer 12 and extends distally from the ultrasonic transducer
12. The preferred method of attachment is a threaded joint. The
ultrasonic applicator may be fabricated from any suitable metallic
material including, for example, titanium alloys, aluminum alloys,
or stainless steel alloys. The preferred material is titanium alloy
Ti6Al4V. Standard machining processes such as lathe or mill
processes can be used.
As mentioned previously, ultrasonic applicators employed in the
present invention are generally round in cross-section at the point
of application of energy to the tissue. These applicators do not
have edges that would focus and disseminate ultrasonic energy in a
manner promoting cutting, but instead are designed to provide
energy in a uniform manner consistent exclusively with the
coagulation of tissue. Indeed, cutting functionality, if needed, is
provided in a separate mechanical component of the surgical
instrument to avoid compromising the design of the ultrasonic
applicator.
The combined length of the ultrasonic transducer 12 and the
ultrasonic applicator 13 must be designed to have the desired
resonant frequency of vibration. The range of vibration frequencies
is generally 20 kHz to 60 kHz. Any vibration frequency in this
range can be utilized.
An elongated support member 14 is releasably attached to the
surgical handle 11 and generally surrounds the ultrasonic
applicator 13 along its length. The elongated support member 14 may
be fabricated from metal or plastic materials. The preferred
material is plastic such as DelrinR (acetyl copolymer) or "ABS"
(acrylonitrile-butadiene-styrene). A clamp 15 with a jaw surface 16
is supported on the distal end of the elongated support member 14.
The clamp may be fabricated from metal or plastic using either
standard machining processes or standard molding process (metal or
plastic). The preferred method and material is a molded metal clamp
mechanism as this provides for maximum stiffness of the part and
the best clamping performance. The jaw surface 16 may have a
variety of cross-sectional shapes, for example, those depicted in
FIGS. 3a-3c. The jaw surface 16 may also have a serrated or grooved
surface to improve grasping performance.
The clamp 15 may be opened and closed relative to the side of the
ultrasonic applicator 13. In FIG. 1a, the clamp is depicted in the
open position. An actuation handle 17 is connected to the surgical
handle 11 and is used to actuate the clamp 15 between the open and
closed positions. A clamp transmission rod 18 connects the
actuation handle 17 and the clamp 15.
An actuation slider 19 is connected to the surgical handle 11 and
is used to advance and retract a cutting element 20 in a direction
parallel or generally parallel to the ultrasonic applicator. The
cutting element 20 may be a stainless steel blade or a formed
cutting shape on the end of a blade connecting rod 21. The blade
connecting rod 21 connects the actuation slider 19 and the cutting
element 20. The connecting rod 21 is preferably fabricated from
stainless steel wire that can be soldered or welded to the cutting
element 20.
FIG. 2 shows a more detailed side-view of the distal end of the
ultrasonic surgical instrument 10 as depicted in FIG. 1a, with the
clamp 15 and associated jaw 16 in the open position relative to the
ultrasonic applicator 13. Surface 32 of the clamp assembly 30 is
separated from surface 31 of the support member 14. The mechanical
cutting tool or blade 20 attached to blade connecting rod 21 is in
the retracted position. The cutting element 20 can be advanced to
cut tissues that have been coagulated between the jaw surface 16
and the ultrasonic applicator 13. (See FIG. 1c.) Thus, the cutting
element 20 is advanced and retracted through the clearance between
the jaw surface 16 and the ultrasonic applicator 13. In a further
embodiment, the clamp 15 and jaw surface 16 may have a vertical
slot through with the edge of the blade also passes as it is
extended and retracted. This would allow the use of a wider
mechanical cutting element and assist in ensuring that the blade
cuts all of the tissue held in the space between the jaw surface
and the ultrasonic applicator. FIG. 1b shows the same ultrasonic
surgical instrument 10 depicted in FIG. 1a, except that the
actuation handle 17 has been rotated to the closed position,
thereby pulling the clamp transmission rod 18 toward the ultrasonic
transducer 12 causing rotation and closing of the clamp 15 relative
to the ultrasonic applicator 13. The movement of the transmission
rod 18 is limited by a stop, in this the contacting of surface 32
of the clamp housing 30 against surface 31 of the support 14. This
occurs so that the jaw face 16 of clamp 15 is "closed" at a
predefined distance or clearance from the surface of ultrasonic
applicator 13. (See FIGS. 3a through 3c.) This distance can be
pre-set and varied by controlling the length of the transmission
rod 18. It is within the skill of the art to provide means so that
this length can be varied by the physician or an assistant during
the course of the surgical procedure without requiring removal of
the surgical instrument from the patient. For example, the
effective length of the rod from the clamp support 30 to the
actuator 17 can be varied by using a rotatable transmission rod
threaded into a portion of the handle 11. In FIG. 1b, the cutting
blade or tool 20 is in the retracted position.
FIG. 1c illustrates the ultrasonic surgical device 10 of FIG. 1a
with the clamp in the closed position and the cutting blade 20 in
the extended position. This was accomplished by the movement of
actuating slider 10 in a direction toward the distal end of the
ultrasonic surgical device, thereby moving the blade connecting rod
21 and the blade 20 in the same direction. As this is accomplished,
the tissue held between the clamp 15 and the ultrasonic applicator
13 is cut by the blade 20.
FIGS. 3a through 3c show three different configurations of the jaw
surface and the predefined clearance.
FIG. 3a is an end-view showing the ultrasonic applicator 13 and the
elongated support member 14 and the clamp 15 in a fully "closed"
position. The jaw surface 16 is concave, which provides for
improved width of tissue coagulation between the jaw surface 16 and
the ultrasonic applicator 13. The predefined clearance 22 is the
space between the jaw surface 16 and the ultrasonic applicator 13
when the clamp 15 is closed to its maximum extent, typically
between about 0.075 to about 1.9 millimeters, and preferably
between about 0.075 and about 0.75 millimeters. Optimal values for
the predefined clearance will vary with intended application.
FIG. 3b is an end-view showing the ultrasonic applicator 13 and the
elongated support member 14 and the clamp 15 in a fully closed
position. The jaw surface 16 is convex which provides for a reduced
width of tissue coagulation with improved transition at the edges
to the uncoagulated tissue. The predefined clearance 22 is the
space between the jaw surface 16 and the ultrasonic applicator 13
when the clamp 15 is fully closed, again typically between about
0.075 to about 1.9 millimeters, and preferably between about 0.075
and about 0.75 millimeters. Optimal values for the predefined
clearance will vary with intended application.
FIG. 3c is an end-view showing the ultrasonic applicator 13 and the
elongated support member 14 and the clamp 15 in a fully closed
position. The jaw surface 16 is flat which provides for a
combination of the results obtained with shapes as shown in FIGS.
2a and 2b. The predefined clearance 22 is the space between the jaw
surface 16 and the ultrasonic applicator 13 when the clamp 15 is
fully closed, typically between about 0.075 to about 1.9
millimeters, and preferably between about 0.075 and about 0.75
millimeters. Optimal values for the predefined clearance will vary
with intended application.
The pre-determined clearance between jaw 16 of clamp 15 and
ultrasonic applicator 13 can be established in a number of ways. As
depicted in FIGS. 1a through 1c and in FIG. 2 this can be
established by a stop of clamp housing surface 32 against surface
31 of the support. Other mechanical stops can be used. One such
stop is depicted in FIG. 4, which illustrates an ultrasonic
surgical device as in FIG. 1a. In this case, however, the stop is
physical element 26 extending from the handle 11 and prohibiting
closure of actuator 17 against the housing. This replaces the
contacting of surfaces 31 and 31 as the stop mechanism. One skilled
in the art, would know how to make the effective length of stop 26
variable, so that the predetermine separation 22 between the jaw
and applicator can also be varied. For example, the stop 26 could
be screwed within a limited range into a hole in the handle 11 so
that it could be effectively lengthened or shortened as desired.
Other techniques for establishing a predefined clearance between
the jaw 16 and the ultrasonic applicator 13 would be known to one
skilled in the art and could be substituted for the examples
described herein.
The present invention also provides an improved method for the
surgical coagulation of animal tissue including locating a portion
of the animal tissue between: (a) an ultrasonic applicator having a
generally round cross-section with a diameter between approximately
2 and 6 millimeters to provide a broad surface for coagulation and
to avoid cutting of the animal tissue and (b) a clamp located
adjacent the ultrasonic tissue. The clamp is then moved toward the
ultrasonic applicator to a predefined clearance of between about
0.075 to about 1.9 millimeters, and preferably between about 0.075
and about 0.75 millimeters, from the ultrasonic applicator to
provide a zone for tissue flow and coagulation. Ultrasonic
vibrations are then applied to the clamped tissue via the
ultrasonic applicator sufficient to cause coagulation of the
tissue. If desired the tissue can then be cut with a separate
mechanical cutting tool as illustrated, for example, in the
drawings and description herein.
As previously noted the device and method of the present invention
are particularly useful in separating and maximizing each of the
coagulation and cutting functions. It also provides a convenient
way for the surgeon to know at all times the position of the clamp
relative to the ultrasonic applicator and the position of the
cutting element or blade. Thus, the surgeon can easily monitor and
focus on these tasks.
The description and drawings contained herein disclose illustrative
embodiments of the invention. Given the benefit of this disclosure,
those skilled in the art will appreciate that various
modifications, alternate constructions, and equivalents may also be
employed to achieve the advantages of the invention. For example,
given the benefit of this disclosure, those skilled in the art will
be able to implement various forms of the clamp, the stop and the
mechanical cutting tool within the spirit of the invention.
Therefore, the invention is not to be limited to the description
and illustrations contained herein, but is defined by the following
claims.
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